Used GRS Bolthorn chassis for Howa/Weatherby 1500 short action. This will work with your 223/308/6.5 rifles. The chassis is 99% condition. The mag release lever was tuned to fit my mags correctly, and EuroOptic is the importer for GRS so I am sure you could get a new lever if you were to find it didn't work for you.

The chassis is $2130 new from EuroOptic.