All my years of dealing with jump cups I vote buy something that does not require pins!
No matter what you attach the pins to the cups with you will loose your pins and always be looking for something to use as a pin.
I know someone who uses the plastic cups with nubs on the back that go into a pin bar. Much easier to use.
I found them several places. Do a search for jump cups and tracks.
Since your one link was Dover I picked the Dover link for here. They actually offer several different styles. Linky
If you go with the type with pins I am betting the plastic are plenty heavy duty enough for your rails. I have metal and they rust and are heavy if you are carrying them around in a bucket.