In 1937, Portugal , with German assistance, went over to 7,9mm cartridge for General Service Issue. They bought in new Machinery from Germany to make the ammo, along with large qty. of RWS and DWM contract 7,9mm cartridges. They also ordered a Mauser rifle,( from Mauser Oberndorf) the M937 and M937A, which was simply a Kar98k with some differences ( sling positions, Front sight ears). At the same time, they contracted with the Germans to rebuild all their M904 (6,5mm) Vergueiro Long rifles into M904/939 Short rilfes, in 7,9mm. The also ordered some more Kar98ks as the "M941" from Mauser Oberndorf.
Both the M937 and M941 Rifles were standard Kar98ks straight off the production line (WaA inspection marks and all, the only difference for the M937s was the sling and Front sight ears.) Receiver crest and Serial Numbering and Matching Bayonets were the only differenec from the Normal Wehrmacht Kar98ks.
The 941 Rifles were simply Portuguese marked Kar98ks, with all German WaA markings, and Serials in the F and G ranges ( up to five digits) specially for Portugal. Towards the end of the contract, Germany took over some for use on the Russian front (Now "RC" mausers). Some escaped the Russians, and ended up in Israel ( late 1940s) and were subsequently converted to 7,62Nato in the 1950s.
The Actual Portuguese deliveries ( of the M41) were mostly never used, and appeared in Milsurp in the 1960/70s as Mint rifles, complete with matching Bayonets. Most ended up in Australia etc as such (GCA 68 in Vogue in USA). WE also go a lot of good condition M37/37A rifles, as well as the bulk of the Vergueiro 04/39 conversions.
Of all the Mauser Kar98k, the most desireable is the M941 in Mint condition, followed by the 1937 made M937 version. All the "old world" finish is on them, as befits an Export rifle.