enclosure size

i have an A avic thats about 1 1/4 inches from the front to the back. what size enclosure should i keep him in? until now i had him in a vertically orientated kritter keeper but i discovered mold in it this morning so i took the tank apart and i'm still thinking of what to keep the spider in. I have another kritter keeper set up but its a little bigger, can i keep him in there? its a little less than a foot high(on is side). Or would this be too big?
any suggestions?

i have kept my avic in a 2 1/2 gal terrarium and it has worked pretty well. it is about 3 1/2 to 4 inches big and seems to like it ok. i have a small piece of glass that i can put across the top of the enclosure if it decides to start webbing all over the top. when i get a digi camera, i will be posting lots of pics of my setups and spiders

At 1 1/4 inches you could keep it in a quart jar. I have kept youngsters up to 2 inches in them successfully.