I have an Adjustable Chalk Branch, with the double-screw forend - I bought it with a pic rail on the front. I replaced it with a 4” ARCA rail, pretty sure MDT brand, and it dropped in no problems.
Definitely don’t stack your arca rail onto a pic rail.
With the Alpine/Adjustable hunter, you should be able to use a significantly longer rail, with the caveat that it’s angled up a bit. Look at SRS if weight is a concern, otherwise can’t go wrong with MDT or RRS or Area419 or…