As far as I know, name change tokens aren't allowed to be bought and sold among users anymore as of late 2014. IMVU didn't want to deal with the amount of reports of people being scammed out of money for tokens they never received. To transfer a nct, a user has to prove the account they want to transfer the token to belongs to them.
IMVU also registers that account as your alt account, in case you thought you could get the account info from said user or vice versa to trick them. If that other person gets banned for whatever reason, your account will get banned as well.
So in summary, all the risk is put on the account who is buying the nct. I'm not saying don't do it, 'cause things might have changed and also cause you're your own person so do you, but I might as well warn you of the probable consequences.
If you're willing to pay someone for one through Paypal, why don't you just purchase the token yourself on IMVU? They accept PayPal as a payment option.