Magnum Research BAR3576 Desert Eagle 357 Mag 6" Matte Black Steel Fits Desert Eagle Mark XIX
https://www.tandktactical.com/shop/761226022886-magnum-research-bar3576-desert-eagle-357-mag-6-matte-black-steel-fits-desert-eagle-mark-xix-7545
https://www.tandktactical.com/web/image/product.template/7545/image_1920?unique=eba08fb
Once you've purchased a Mark XIX Desert Eagle you can change the barrel length in seconds, if you have the appropriate components in hand.