I recently was looking for a hood for an old Marlin 39a that I have had for 35 years and all I could find was the wide angle one, So I went out to the shop yesterday and got a piece of round stock 5/8" od and drilled a 3/8 hole thru then chucked a 3 flute endmill in the chuck and ran it through, it cut a .475 dia hole next turned the od to .530, cut off faced both ends sq. to .630 OAL, milled the slot in the bottom to .305 width and dressed with a file until it would just start in the slots, heated it dull red with Mapp torch and dropped it in some used oil, PRESTO a sight hood just like I wanted in about an hours time, blue even matches. Jeff