Doors and Windows - Non-standard size basement storm windows

Hi. I have an older home (built in the '30s) with the old steel framed windows in the basement. They are drafty and certainly not the most secure. I am considering framing out the windows with wood and attaching storm windows into the handmade frame. However, nobody seems to sell basic cheap custom built storm windows. Home Depot carries ones that are about $50/window. Our local Lowe's carries the cheapy ones (about $15/window), but they come in standard sizes--and none of which will fit my windows. My window opening is roughly 39 inches wide and 21 inches tall.

I am hoping to install the really cheap ones, basically to cut down on the draftiness and keep out the dirt and debris that is currently coming in. I do not want to remove the old steel framed windows. I am even considering, with great dread, making my own windows out of plexiglass (ugh).

I'm up for any suggestions... Hopefully, someone might point me in the right direction to get those cheapo windows made in the funky sizes I need. Thanks!

hi
check a local salvage yard you might find some
or check with a window company sometime the have defective ones or special order where cancelled.

cheers

pg