In addition to the battery grip, I have cabled remotes LA-50 and LA-500, a number of Contax UV, Protection, and Polarizing filters in varying sizes up to 95mm, compact flash TLA 200 (TTL, originally for G1/G2 but obviously work here too), external Power Pack P-8, film back holder MFB-1 and an extra MFB-1A 120/200 film spool cartridge. I also have a number of brand new hoods for Contax 645 and N system lenses. These items are boxed in original packaging, either brand new, or with very little use.
Let me know what you are interested in and I can research a fair price.