Yeah, generally people sub in bb rows. That's what I did because of issues with my shoulders when "catching" the bar after the rack. Add some chins as well and you'll be hitting pretty much all the same muscles.
Or you could do power high-pulls. It's a clean without the rack, and tell your current gym that its a completely different exercise, and unless they have expressly written it into your membership contract that you can't power high pull that they can suck your almighty-powerful balls.
Infact, unless it expressly states in your membership contract that your membership is conditional to certain things, such as not power-cleaning, tell them they can suck your power-cleaning balls.
If it all goes pear-shaped, ask for a phone book so that you can just quickly call your lawyer and ask him how he thinks this is going to go down in court.
If they don't fall for it, then scream as many profanities as possible and have a couple of weeks break until your own equipment arrives. Then enjoy those power cleans. Make sure in a few years time when you are massivley ripped you go back to the gym and tell them to suck your ripped balls.
Hope this advice helps.