I don't think that there are any current 1-rack sampelrs available today. The last sampler I can remember that was a 1-unit rack was the Roland S-760 which is a little underfeatured compared to the E-mu's. It also came out originally in the early 90's.
Anyway, all of the samplers today are at least more than one rack space because everyone wants expandability. The manufacturers also like expandability because:
1. They can sell options for them, which increases their sales.
2. They can leave options out to bring the price down at the store, making it more affordable for more people, also increasing sales.
Looks like you need a bigger rack.