If you are looking for a similar sound, consider sticking with capacitor-coupled amps/receivers. This is an earlier solid state design, with blocking capacitors in the output path, and results in a sound that most folks feel is warmer, at the price of some detail and distortion (as compared to direct-coupled amps)..
Generally, by the mid to later 70s, the big name manufacturers had moved just about completely from cap coupled to direct coupled designs. So you would be looking at units from the late 60's and early 70s. Note that some manufacturers mixed cap-coupled and direct-coupled designs within the same product line, with the lower-powered units being cap-coupled and the higher-powered units being direct coupled.
If you end up looking at direct coupled amps, you will find that each manufacturer's early models sound more similar to your 5000 and 2000X than do later versions. For example, the Pioneer SX-828 (and the whole SX-x2x series) has a looser, less precise, warmer sound than, for instance the SX-850, which was two generations later. Or even vs the SX-838, which was one generation later.
There is a thread on AK which is built around building a list of cap coupled receivers/amps; it may give you an idea of units to further research and consider. See here:
https://audiokarma.org/forums/index...e-receivers-and-integrated-amplifiers.912075/
A couple of Kenwood receivers that you might like are the KR-7200 or the KR-7600 (direct coupled). The 2230 is a classic Marantz cap-coupled receiver, and the 1060 is its equally satisfying integrated amp sibling.