Thanks for the tips. Very helpful. Not sure if I want to tackle this myself.
I did receive this very helpful info from the writer of rem870.com:
This will take some time, parts and tools but it can be fixed.
The broken part is an ejector, you will need to remove the broken one.
Here is video how my friend and I replaced one rivet and ejector spring:
http://www.rem870.com/2011/10/25/remington-870-ejector-spring-replacement/
You will need to remove 2 rivets, remove the broken ejector and spring.
This can be done using rivet cutter or something else.
You will need to get 2 rivets, ejector and ejector spring (not sure if the
old one will be ok).
http://www.brownells.com/.aspx/pid=0/sid=2/schematicsdetail/870-Express
Parts #15, 14, 13 and 77.
We have used this set of tools:
http://www.brownells.com/.aspx/pid=653/Product/REMINGTON-870-RIVET-STAKING-TOOL-SET
This tool-set has good instructions included.
After the installation you will need to do something to fix shotgun
coating where new rivets are installed.
I would be greateful if you could take photos of the repair process to
show other owners how to fix this problem. All contributors receive my new
eBook about Remington 870
If you will have any additional questions, please, don't hesitate to
contact me.
Thanks,
Vitaly.