Turns out that my existing Foscam wi-fi cameras can be accessed via my existing port forwarding on http. It just took some research to find the syntax:
A working example - my guest bedroom, aka cat prison
This is a visitor login, so tilt/swivel commands are not available (you're stuck with whatever view I last used)
Front north side of the house:
"Rugcam" - center of the livingroom:
Real Soon Now I'll be updating my web site to use these:
In other news the replacement router has been delivered, when I get home tonight I'll set it up and hopefully all 8 webcams will be back online.
And I can return the rtsp-capable camera.