Last year people were giving them away for free towards the end of the holiday. Haven't seen people selling them or giving them away yet this year though. Once the holiday ends you can no longer re-mount them... So if you're wanting to ride a polar bear all year make sure to get one on a char that doesn't need to dismount (and doesn't die) like a crafter/bod char for example. Also be careful when double clicking on doors so you don't double click yourself and dismount.
