Springfield's far from the only one with high priced(overpriced) accessories. Lots of other firearms manufacturer's are the same way.
If your looking for an accessory or part for your M14 or M1A, ask us here or on the M14 forum first.
As for the price of an M1A, sorry but if you think it's overpriced than take a look at the competition. Starting prices for a basic rack grade commercial M14 from anybody else like LRB, Smith, or Fulton are well above SA's and aren't neccessarily going to do anything more or better. You'll hear people talk usgi this and usgi that bullshit all day, but there's nothing to really base them on being better on average more than just someone's opinion and there's a very large amount of very happy M1A owners.
Atleast with an M1A you'll get a lifetime warranty which in the long run, makes it a much better deal for your money than another commercial M14. Just don't buy accessories straight from a manufacturer unless you know it's a good deal.
My suggestion if you want a good bipod setup is to go Harris or if you want something a little more modern, than mount a Versa-pod swivel rail or another picattiny rail option and buy a nice Versa-pod, GG&G or Tango down bipod to attach to it.