Your recurve is probably cut to center, and I'll assume a low-stretch string. Given your draw weight at 28 inches, and a desired point weight of 125 grains or so, 11/32 POC or Doug fir shafts spined about 55-60# and cut to 29 inches BOP (30 inches full length minus an inch for the taper) should about do it. May have to go up 5# of spine for the 175 grain heads. Finished and fletched (and depending on point weight), these will come in at 500 to 550 grain arrows in POC, usually a little heavier in Doug fir.