The 301 is awesome but all the walking feet currently sold on the market are too large and no matter what people will tell you the don't work like the feet are engineered to. The feed dogs on the walking feet don't mesh properly with the 301 feed dogs. Will they 'work'? Yes, they will fit, but not work properly. I own 5, 301's because they free motion quilt wonderfully. You can lower the foot pressure for straight quilting and you may not need a walking foot. The 301 would be my first Vintage Singer for all around large throat space and stitch quality.
My second pick would be a class 15 machine. It will give you great FMQing, and the ability to use any low shank feet or walking feet on the market.
The 201's have a horizontal bobbin case and are not the best machine for free motion quilting.