Hi J.!
We have the same issue with my daughter's room being atleast 2-6 degrees cooler at all times than the rest of the house. We have woken up where her temperature rectally is 91 degrees and she had to go to the hospital because of hypothermia to be re-warmed. (not sure if the hypothermia is due to anaphylactic reactions though, which is what we actually believe but the cold room prob does not help)
Anyhow, we just purchased from Farm and Fleet in Woodstock the Holmes radiator looking one that is filled with water. It is not the oil filled one since I was too leery about it. It has 3 different wattage settings (to help save electricity)and also a temperature setting so you can set it and it will turn itself off when the room reaches a certain warmth, not temperature. It also has more safety features than I have seen on any other one, including the tip over shut off feature. My daughters room is now warmer than the rest of the house!!!!! I have been able to turn my heater back down to 68 and her room is 74 now with her heater- we put a thermometer in there to check. Now, I am hoping we can finally save some gas money :)
The only bad thing I have found with this is that it is hot to the touch, although it does not seem to heat up the carpet it is on or anything near it. We have it about 2 feet away from everything to keep it even more safe (I am a worry wart). When my daughter wakes up in the morning we shut it off and turn it on about 30 minutes before nap time to get her room back up to the temp. we want it at. She already knows HOT and will not go near it but even if she did it will not blister her it is just like touching the front of the oven when baking- make you pull away your hand and you will feel it for a few minutes.
Good luck keeping your baby warm! I know how frustrating it can be! No matter which one you choose please do get an extra smoke/fire detector for that room- just to be on the safe side!
Blessings to you and yours!