reetings,
eBay? (Depends on age I guess) local camera shop??
(More recent gear) >> KEH, Adorama and B&H all have excellent used departments.
~Rick
Bay Area - CA
~R5 C (1.0.7.1) ~RF Trinity, ~RF 100 Macro, ~RF 100~400, ~RF 100~500, ~RF 200-800 +RF 1.4x TC, BG-R10, 430EX III-RT ~DxO PhotoLab Elite ~DaVinci Resolve Studio ~ImageClass MF644Cdw/MF656Cdw ~Pixel 8 ~CarePaks Are Worth It
