Finnish company Paukatti Oy published aftermarket chassis for Sako TRG 22/42 in IWA 2019.
here is lot of features but here is some I copied from website: http://pautac.fi/tuote/pautac-p-a-c-precision-alloy-chassis/
Easy to install with drop-in design for TRG 22/42
Over the bold folding stock
Fixed stock version available
Chassis design to compatible with TRG’s factory trigger assembly and magazines
Full length monolithic 20 MOA STANAG 4694 NATO Accessory Rail for optical and electro-optical devices
Free float MLOK fore-end and multiple mounting point for M-Lok rails and accessories
Compatible with most AR pistol grips
MIL-A-8625F anodized finish in black, Cerakote available
CNC Machined from solid billet of 7075 alloy
Thumb rests on both sides of the chassis
Multiple QD sling flush mount socket in buttstock
Cheekpiece height adjustable and lockable
Buttstock length and height adjustable and lockable
Chassis will fit also to TRG 21 since action and trigger assembly is same as in TRG 22. Fixed and folding stock options are available.