WTB Altec 428-8A 10" guitar speakers

[wildheritage]

Hi Everyone,
i Have been looking for a long time now to buy 1970s Altec 428-8A 10" guitar speakers for my Ampeg VT-40. These speakers were an upgrade back in the day. I'd appreciate any feedback on how to find them. I keep endlessly searching ebay, craigslist and facebook. But no listings.
I tried to contact Great Plains Audio, but they do not return emails or calls.
Thank for all and any help.

 

[loudnoises]

A wanted ad in Bartertown might be worth a try.

Do you mean the 425-8a?

 

[OBMG74]

Which would require a subscription which has many benefits in addition to Barter Town.