I should clarify: Unlimited data is grandfathered in for those who have it. If you buy a subsidised phone, you lose it. So, no subsidised phones for me.

All the 4G LTE phones for Verizon use a SIM card of some form or other. When I switched from 3G unlimited data on a Blackberry to a HTC Thunderbolt, I just went to my Verizon store and got a SIM card for it, and plugged it in, and it's connected. As the unlimited data is no longer offered, I won't buy subsidised phones anymore, so I'll just switch SIMs from phone to phone. Have you talked to a manager at one of the Verizon stores, or a higher-tier supervisor on their customer service line? One of them should be able to help you with this.