Try e-gunparts.com, gun shows, want ads.
GUNPARTSCORP.com and JACKFIRSTGUN.com carry lots of parts.
Try e-gunparts.com
10-100
20-50 USD
10-100
Parts for the Rohm Model 66 .22 Magnum can often be found through specialized gun parts retailers, online auction sites, or forums dedicated to firearms. Websites like GunBroker, Numrich Gun Parts, or eBay may have listings for specific components. Additionally, reaching out to gunsmiths or local firearm shops that deal with vintage or less common firearms can yield helpful resources. It's important to ensure any parts purchased are compatible and legal in your area.
10-30 usd
Best left to a gunsmith
Gun Parts Corporation (AKA Numrich) is the source for replacement parts for most obsolete firearms http://www.e-gunparts.com/productschem.asp?chrMasterModel=1980z66 they list all the standard Model 66 barrel lengths
this rifle should be marked .22S,.22L,and .22LR.
20-100 or so
About $150 if its in GREAT condition and has both the cylinders .22 and .22 magnum.