Sadly, no I did not. That was another one of the drawbacks to my purchase of this Plus.
Finding a keyboard and mouse in platinum will be easier then finding a pair in beige. I'd ask in the trading post. I'm sure someone has a spare.
I also remember someone posting in the Trading Post that they had posted a pair on eBay and the price wasn't bad. I forget who it was and if it was beige or platinum.