Boss 338 ?'s

[cdog73]

My plans are to lower my 71' C10 approx. 5/7 with a set of Boss 338's. I wanted to go with 20's up front and 22's out back but as far as i can tell everywhere i have called says there are no 22's to be found in gunmetal with the polished lip. Anyone know where i might find a set??? Next thing is if I have to go with a set of 20's all the way around with 8.5 up front and 10 out back should i go with the 5.5 offset or the 6.25. Im getting mixed answers. The reason i ask is because my plans are to go with an extreme Porterbuilt drop next year and i want the wheels to work with the truck now on the static drop and also with the extreme drop next year.Planning on going 255/40/20 up front with a 295/40/20 out back if i go with the 20's all the way around. If i go with the 22's out back ill go 255/40/20 up front and 295/35/22 in the rear. I f any of this dont sound right please let me know. Also if anyone knows the best place to get the 338's from that may have the 22's please let me know. Im in Indiana so closer the location the better. Thanks guys!! Any suggestions are welcomed