I'm not a gunsmith, but with envy for such with tool talents! But combo of reading a fair amount and "hands on" with a variety in mauser milsurps & such based sporters. I do concur with much said here, particularly including many of the commercial brands and military iterations mentioned. There are just a heck of a lot of nice commercial rifles out there to be had yet at reasonable prices. A big part of 'the deal' in such expertise expressed here, in picking & choosing; knowing how to evaluate the prospective purchase. Wheat from chafe! Then too, some of the Bubba categories. Most where either good truck guns to "salvageable" components at least. I'm with more than my share of the Bubba-supreme Enfields - SMLE & Model '17; Springfield/Remington '03, mausers, 96 & 98 iterations.
I do particularly concur that the Sears Model 50 'was' a sleeper for ages! Now, not so much based on in-crowd as here, attention & climbing prices. The Husqvarna series in classic FN mauser 640 series and 1600 small ring actions as yet sometimes in bargain territory! In terms of "truck guns", I see an entirely legitimate category; the term descriptively put! Just a lot of strong, moderate abuse capable, not to worry about minor scrapes & scratches as integral to use. For me such as the '17 Enfield, as 'tamed' with 'trimming, heavy around the ears' smile and maybe replacing the circumcised military stock, if offensive! "Celebrating" ('in-term') cock on closing simplicity/ruggedness, five round "distended belly" magazine; big solid, mammy-jammy action! Truck guns with absolutely their legitimate place in the world of rifles; practical side!

Moving to the interesting Doumolin mauser action listing. Reading the advisory, with red flags. To me, picturing an unfinished action itself. Such differing from expectation associated with purchasing such as a FN action in fifties era. The "D" action with considerable recommended work, beyond barrel fitment. In many ways paralleling blueprinting the action, but more extensively and moving beyond! The net caveat inferring an 'action in the rough'. A 'by the way...' concerning feed rails and feed ramp, exemplary. But adding squaring not just receiver face and "lapping" lugs into full contact. Bolt face too! I take such cautions collectively as reflecting actions themselves considerably "semi-finished". Such well beyond barrel 'fitment' and requiring considerable additional skilled/precision machine work.
Net, net here, an 'informed' "be careful what you wish for"!

A great thread here Gentlemen and perhaps to suggest sme of the more obtuse actions as good candidate sporters, as is or reinvented! My contribution the quality Schultz Models 60, 65 & 68; aft locking bolt rifles!

Best& Stay Safe!
John