I’m pretty sure I’m wholly unqualified to answer that. But given the experience of those that have chimed in, I think I may just give melamine a try. It’s cheap so if it doesn’t work, I can pitch it without too much heartbreak.
(https://www.homedepot.com/p/3-4-in-x-23-3-4-in-x-4-ft-White-Melamine-Shelf-Board-252297/202089063)
I think that’s probably a really good idea!
you can also put a coat of wax on the bottom of your existing sled to improve it’s movement.
Perhaps a Formica sink cutout?
I did a little giggling for Corian sink cutout. Supposedly if you ask a few cabinet shops you might be able to find one for little or nothing. Haven’t tried it but I will when we get to the big city, it turns nice. I got a free granite cutout that way, nice for gluing and a low budget/low accuracy surface plate that’s good enough for woodworking