Baird, Rohn, Commscope and several others have many NPRM options. Be sure to also investigate the pads, safety tethers, ballast and be prepared for a hefty price tag.
Usually several local business will have an unused NPRM that is free for the asking and cost of removal. What costs thousands of dollars new is usually free if you confidently approach prepared with a professional removal plan. You should hire a boom truck to avoid the traffic across the roof and insurance issues. Remove the equipment quickly and with minimal impact to the facility.
Make contact with a crane operator before you need the service so you know the cost and lifting / delivery services they can provide. Most businesses will not allow a non-tradesman or uninsured person on their roof. They are unlikely to want disassembly and roping parts down to the ground. Most would rather leave dishes on the roof than be bothered with any hassle for removal.
Ballast removal may be the biggest hassle of removing a NPRM. Crane operators often can provide a bucket or sling to move loose materials. Be prepared to walk away from a find if the removal will damage the roof. Often NPRMs have sealant applied over the years and I would walk away from a NPRM knowing in advance that removal would necessitate a repair. Be prepared to address any damage that might occur during removal. I usually will be in contact with the building management in advance to know who to contact in case of any issue and assure them that I will not remove if it will cause any roof or structural problems.
Check with shut-down auto dealerships, traders, brokers, churches, roofers, etc. Often a commercial real estate agent will be your best friend if you reward them with a finders fee or gift certificate for providing a contact or negotiating a removal.
Brian Gohl
Titanium Satellite