I dont think A600 accelerators are THAT rare. Yours have some big hard drives though, so thats a good bonus. Your best bet is probably to get on ebay and look at completed sales to get an idea what the high and low end sale prices are. It's hard to give any serious values on old Amiga stuff, because you can get on ebay where there are lots of collectors willing to pay $200 for a computer, while someone else can find the exact same model computer at a thrift store for $10, or get it free from someone who just wants someone to "get this junk out of my closet." Its worth whatever someone will pay for it, and there is a big range in that.
Ebay will probably get you the most money, if thats what you're after.