I haven't used a WMO in a long time but you might find one decently priced on ebay. You could also take this opportunity to try some new products. I've been using the G400 for a few years it's not bad.
It's polish site but the seller told that he can send abroad.
This mouse costs 39.99 PLN which is 9.61 EUR or 10.82 USD.
I don't know how much shipping will cost.
In description u can see that is legit and original MS WMO 1.1a and it's used. NOT NEW. But u have 6 moths warranty.
I bought that wmo from this guy about year ago and it's working well, i can paste some pic's of it here if you are not sure if it's real and original wmo.