I like the first set better. They're located in the USA instead of China. Probably still made in China though. No telling if they will fit without modification. It has been a long time since I've seen a VT foot-peg assembly. I know that RAASK makes a pair of rear-sets for the FT500 Ascot, but I'm not sure about the VT500 Ascot.
I modified my foot-pegs on my FT500 by cutting off the old peg until it was just a stub that hinged in the foot-peg mount. Then I welded a set of dirt bike pegs to the stub. This raised the bottom of the pegs about an inch higher than the original pegs for better ground clearance in the turns.
Whatever you do... You want to maintain the pivoting feature in case you touch a peg to the ground while leaning through a turn. You want that peg to pivot up & out of the way instead of digging in to the asphalt.
Good luck
J.