I know there have been several discussions about FMQ with a 301. Some older, some newer:
Can someone tell me what free motion foot to get for my Singer 301
Singer 301A darning foot?
Anyone FMQ on slant needle machine?
Singer 301 FMQ Feet
I don't FMQ, but I have used my slant shank machines for repair some shirts and really liked them for that. I used a beehive spring that goes around the needle for darning some socks. It worked really well.
I'm not sure about a quarter inch foot for the slant shank, maybe sew-classic.com?? There are also seam guides that screw on to the bed, magnetic seam guide and of course tape and post-it note pads or moleskin.
Janey - Neat people never make the exciting discoveries I do.