RetroSpy Technologies produces a range of retro (Vintage) hardware products that are of interest for the KIM-1/SYM-1/AIM 65 owner. Also the PAL-1 user may benefit from the products!
Retrospy is inspired by the Corsham Technologies products and since Bob Applegate is no more among us, produces similar/inspired products.

I bought several products from RetroSpy.
KIM-1 RAM/ROM Board
MOS 6530 Replacement for the KIM-1 SBC
PAL-1 Motherboard Expansion Kit
Bus extender
Other interesting KIM-1/AIM 65/SYM- related boards on the Retrospy shop:
AIM 65 I/O board
SYM-1 I/O board
SYM-1 SymDos I/O board
SYM-1/AIM-65 RAM/ROM board
KIM-1 I/O board
2532 to 2764 EPROM adapter
SD Card Storage System (like the Corsham one)

I should have bought he KIM I/O card also, for the 1541 connector, next time!