Good turntable from the 3 point suspended minimalist days. I'd check that the suspension works correctly and is well setup, the speed is stable ( replace belt if not) and simply enjoy it. The competition in the early 80s in the UK for turntables beyond the £125 entry level price point was quite fierce. This was a good thing as it forced manufacturers to take a *sound first* approach where it matters most...leave out expensive automation and bells and whistles that had nothing to do with sound reproduction. Even a speed change switch was considered a luxury. Auto stop ? forget it.
The Dual CS-505-2, Rega Planar 2/ Rotel Rp-830 and a few others were considered a *minimum* standard of vinyl replay for anyone looking to extract the most information from a good pressing on a very tight budget.. Beyond that price point was the £200 plateau. That is where the fun really began for the cash strapped music lover wanting to make the most of a modest cartridge upgrade. The heirachy of what made a minimalist turntable sound good :, isolation from vibration first ; a good quality , well finsihed main bearing ; and a half decent tonearm free from bearing chatter, binding or excessive freeplay was considered the logical way to get better sound on a limited budget. The cartridge quality was considered last and its cost was generally agreed to be no more than about 20% of the total turntable package at this level.
'Garbage in..garbage out' being the UK approach , it made sense that any £20 -£40 cartridge of decent spec...would actually need a decent quality £200 turntable to do it justice. Beyond that...it made more sense to upgrade the turntable first before strapping on more expensive cartridges.
The Walker CJ-55 ( and I think later CJ58 ?) would have battled it out with the likes of the Ariston RD80 ( and later RD60), AR-EB-101, Rega Planar 3, Systemdek XII, See Revolver, Thorens TD-160 mkIV, Rotel RP-850, RP-855 and a few others for a customer's hard earned cash.
At this price point , manufacturers tended to stick with either of two belt drive formulas.
Usually it was the simple fixed plinth , belt drive concept ( i.e like the Rega & Rotel, Revolver) and then bolt on the best arm they could manage in that price point. Alternatively, they might attempt a balance between offering more isolation from external vibration via a semi or fully suspended subchassis and compromise slightly on the tonearm in terms of overall quality.
Of that list of turntables above...there wasn't really a clear winner in terms of outright performance.They all performed to a good standard expected from a £200 turntable ( circa mid 1980s prices) so it was more a personal choice which you preferred. Missing from that list is the Technics 1200 which wasn't often taken seriously as a good turntable... mostly because of it's DJ association and Hi-Fi press snobbery ,but, it was in fact right there in the mix , albeit slightly more expensive.
The good news is... these turntables can still hold their own today...and I'm not 100 % sure there have been any great strides in performance over similarly priced models available today ( price adjusted for 40 years inflation).
So...find a good cartridge that matches the tonearm's effective mass..dial it in to Baerwald (or Stevenson if you prefer) and go from there.
You could try a tonearm swap later on but I wouldn't go too far beyond something like a circa 90s Rega RB-250, RB300 or Linn Basik..and even then...differences might not be night and day.
It's hard to ignore the benefits of a 3 point suspended deck in term of sound...and I'm not sure if any that are still made today...can compete on price per sound ratio with the likes of the CJ-55 Ariston RD80 and RD60 or Systemdek XII or Thorens TD-160 mkIV. Even back then... you were looking at a Heybrook TT/2 or perhaps Manticore Mantra, Logic DM-101, Systemdek IV , Michell Gyrodek or one of the more spendy Thorens model to gain any real advantages over what these humble, yet well engineered turntables were capable of. Then as now...good machining has never been cheap.