Well, that's kind of what a steem power delegation is, but of course the problem is that it takes days to pull back the delegation.  At one time, you could rent 30 or 90 day delegations from @blocktrades, but I haven't checked on that recently.

Another option would be for someone to create a slew of accounts like dvote1, dvote2, ..., dvoteN, and rent out the posting keys for a period of time.  They'd have to set their rates high enough to make up for the recharging period after you give the keys back, though, so that's basically the same thing.

Third option, a paid service that adds their bot to your voting trail for a specified period of time.  You vote at 1% and the bot follows along and votes after you at an agreed percentage.  The recharge time still applies, though.

Seems like you'd have to pay crazy-high prices or buy for something like 10 days at a minimum for it to be worthwhile for the seller.