I have a Shimano Arabesque 600 (circa 1982??) rear derailleur that is for sale probably for spare parts only.
I'd say it has been caught in the rear wheel and has cracked the spring cover, since then the bike has sat idle.
Too good tho throw out, probably to bad to list on eBay so if someone needs it for parts. It's $US5 plus $US10 shipping.
Thanks
Anthony Kinder
Perth, Western Australia