Will the standard Power Custom Free spin pawl work on the new 5 shot SBH??

No, it's a different geometry so it's not a drop in. The stock pawl can be modified into a free-wheeling unit by a competent 'smith.

So, I got my 480 when they first came out and Power Custom does make a "longer" FSP for this revolver. My gunsmith had to call because it did not show online. Max is correct that it is not a "drop in", it does take some massaging from a gunsmith. Good Shooting