Chris,
* Your 1936 S/42 should have a small, lower case, suffix letter beneath the frame's S/N.
* The proper main mag for an Army 1936 S/42 P.08 after the "m" suffix block would be a folded & crimped, blued S/Mtl tube containing a coiled spring w/ a single side pinned Aluminum base plug bearing the S/N, suffix letter, & a small droop winged eagle/63 acceptance stamp. The follower is also bright. The reserve mag is the same as above w/ the added "+" stamp to the base plug.
* Before the Army "m" block, the tube would be un-blued (bright). A transition range in the "m-o" block was likely for bright tube to blued tube as excess white tubes were being used up by Mauser.
* The 1936 holster should be easier to find ( and less expensive) than a 1935 PT.08 all else being equal. The 1936 PT.08 will have a maker's name, city and year marked between the two belt loop, a droop winged Eagle/WaA### Army Acceptance Stamp, and NO P.08 mark on the rear side.
* A search on this Forum may reveal pictures of a 1936 holster example.
* Trust this helps.