I have done a lot of work on PDP-11s and with RSX. I've modified the DECUS C-compiler, improved SRD (the DECUS tool), written a Z-machine interpreter (ZEMU), fixed KERMIT, written device drivers and a TCP/IP suite for RSX, and done a number of other things.
I maintain hardware for the Update Computer Club, who have a couple of PDP-11/70 systems, as well as some other smaller PDP-11s, and I have a PDP-11/93 at home.
If you need help with PDP-11's, RSX, device drivers, TCP/IP, or probably anything else, just contact me at email@example.com for more information and/or help. I have been working with RSX for 30 years by now, and do know what I'm doing. I live in Switzerland, but will travel all over the world to help you out.
You can also look at Madame, a PDP-11/74 (emulated) which is running RSX-11M-PLUS, and my TCP/IP suite and a web server that I've written.