Your rifle is obviously a commercial version of the military Mauser 98 action (left receiver wall thumb notch), as done by Heym, with integral receiver scope mount dovetails, etc.
I have a similar version, done in England by Parker-Hale.
Heym most likely didn't apply any sort of model designation to your rifle, other than "Sporting Rifle", because I doubt they made more than the single type of boltgun in the 60's - being predominately a break-open action gun maker.
IIRC, 1" = 20mm or 22mm. Commercially-made spacers are available that will allow you to install a 1" scope in the 26mm rings - but it's probably easier/cheaper to just make two pair, an upper/lower for each ring.
In the mid-1970's, I owned a new Mauser 3000, however - which was marked/made by Heym - so the company's evidently had close ties to the Mauser firm for a long time, even if only for leasing Mauser's design(s).
Heym was founded in Suhl, Germany by Friedrich Wilhelm Heym in July 1865.
The company expanded producing drillings, shotguns, and over and under rifle-shotgun combinations.
Russia was their most important export market until 1914.
In 1912, Adolf Heym assumed management of the company, and began shifting the export market from Russia to the USA.
August Heym assumed management of the company in 1920, and began production of Anson & Deeley Drillings, double rifle drillings, drillings with three triggers, double rifles, and rifle shotgun combination guns.
Following World War II in 1945, Heym made a new start in the West Germany.
The factory moved to Ostheim in the Rhön/ Lower Franconia, building cuckoo clocks, slide rules, and spinning wheels, among various other products.
Heym built a new factory in Münnerstadt/ Lower Franconia, Germany in 1952 and transferred manufacturing to this site.
Rolf Heym took over management of the company in 1963 until his death in 1972.
Safety rifle/shotgun Mod. 22F
Repeating rifle, Mod. SR 10
Repeating rifle, Mod. SR 40 short action
Mod. Mauser 3000
Repeating rifle SR 20
Over and under rifle Mod. 55
Side lock drilling Mod. 37
Block action rifle (HEYM/RUGER) HR 30 / 38
Double rifle(s), Mod. 80 / 88
Last edited by PetahW; November 10, 2009 at 05:30 PM.