Hi Solarken - I have the same issue - Wefco Rubber - still in business - have the rail 0422G and the insert 4107 BUT only in black - discontinued other color options during Covid. But paint allegedly does work. But also a min of 25 ft,
Hammer insert into place as much as possible square up ends of rail then cut a piece of PVC pipe of closest diameter to fit (heat gun if necessary), then glue in place with construction adhesive. Should pass the 10 foot test.
