No you can get poly in 100', 200', 300', 400, & 500' rolls. You need to use a male x insert adapter that is made of the same material the pump is. For example, stainless pump, stainless adapter. But for a few dollars more you can buy sch 80.
I have heard of people screwing sch 80 together on the ground and running it in, but I have never done it.
Personally, I hate seeing a submersible in a well hung on poly. The stuff is designed for being in a trench. Why? Go pull out a few hundred feet of poly. In addition to the stuff having a memory and wanting to curl up, it's all over the yard, in the dirt & dog crap, the wire gets knots in it...... Sch 80 can be laid out on blocks to keep it out of the dirt, you can get the wire taped off so there is no slack, the wire can be rolled up on a reel when the pump needs to be changed....it's just makes for a nicer, cleaner, more professional installation with a far less chance of picking up and transferring surface contamination to the well.