a/c wall sleeve issue

[towncarblue]

i recently moved into a a home that is 10years old. it has these friedrich wall sleve a/c units[ 16.75"H x 27.00"W 18.00"D]. the a/c in them are old and need to be replaced. ive seen the prices of these units and they are high and stick into the room by 7 inches. is it possible to just buy a window/wall unit and put it in there[ they are smaller than the current ones ].
does anyone sell a kit to compensate for the gaps on the sides?

[HayZee518]

I haven't see anything in the box stores to use for adapters, most would be custom installs anyway. 2X4's with long sheetrock screws would probably work.

[tudor]

If you shop around some for a through-the-wall unit, you can probably find one that's not too costly. They cool much better (are bigger) than window units and come with space adapters. I got an 8000 btu one for just over $360 at the start of the summer. I think they will be cheaper now too.