Hi,
I'm not sure if we can help you, and the question is past due!
The only way to find someone who rents this equipment is to ask around, and you have probably already done this...
You may want to contact a manufacturer for advice, as they may sell vacuums to people who rent them.
Here's one in New Jersey:
Elgee Manufacturing Company, Inc.
225 Stirling Road
Warren, NJ 07059
1-800-742-0400
sales@elgee.com
Try superpages.com. Search for "rent vacuum" and make a few calls.
I found one web page that mentioned "a very few" companies rent HEPA vacuums:
http://www.buyersresource.com/417.html
Also, Googling "lead abatement residential how to" leads to some good links. Here's a few:
http://www.cleaninglink.com/Safety_Library/Lead_Abatement_Encapsulation.htm
Permanent removal, according to this website, requires a certified lead abatement contractor:
http://apartments.about.com/library/articles/bl_lead.htm
Check out the epa.gov website:
http://www.epa.gov/opptintr/lead/leadinfo.htm
In general, the information is quite scattered.
Good luck.