Condenser:
Yours is the DII, not the DIIV, it appears. I suspect it is the older one with the thinner (steel?) rails, not the newer version with the larger aluminum rails and the crank? The DIIV had a V (that is, a variable condenser) which is in under the lamp. There were brackets where you would slide a smaller condenser in, which changed the condensers focus. Prior to that, they supplied a smaller condenser in the same sized can, which you had to change. The condenser is matched to the focal length of the lens. If you print 35mm with your 135mm lens (assuming that is what you have), you'll probably be able to make a 5x7 print, unless you turn the enlarger around and print on the floor (not much fun, unless you are making a 30x40, which you won't be able to do with your setup). If you change the lens to a shorter focal length you are supposed to use the smaller condenser or the variable. You could try it and see what you get, though.
One thing you could do is to put a circular piece of opal glass under the condensers in the "can". That would, in effect, change what you have to a diffusion enlarger and it probably wouldn't matter that the condenser is mismatched. It will slow your exposures. Otherwise, you may be able to find the other condenser, but it probably won't come when you whistle. I know I don't have one. I've been using a DIIIV since 1964.