Looking for a replacement manual transmission

I have a 2006 Aveo with 5 sp MT that, up until now, has been a pretty good car. I just had a bizarre transmission failure though where the housing cracked (part of it actually broke off around the shift cable!). So I'm looking at a replacement (was told that was cheaper than replacing the part) and am trying to track down a used one. Fortunately there are a lot available on eBay at decent prices, but before buying there I just wanted to ask if there was anything (other than model year) I needed to look for to identify the correct tranny. Is there? I ask because I've been told (warned) that manufacturers sometimes make several versions of the same transmission for different vehicles, and even though they're technically interchangeable, still have differences (like speedometer connections, etc). I don't think that's the case here, but thought it was worth asking before pulling the trigger on one.

Thanks for any feedback on this. I appreciate it.

Call dealership and give them your vin they should be able to tell you which aisin to go with and what last I believe 3 digits of the serial number on the tranny to watch out for. Its your best bet. Good luck with that.

Actually I did call the dealer, and the only information he could find on the transmission was the designation "D16 SW/R L91-MLM". But he also said there should be an 8 digit number on the bell housing, and I would need to get that off the bell housing itself as he didn't have that information.

So which do I need to correctly ID the transmission - the "L91-MLM" or the number off the bell housing?

Thanks for the help!