Hi, the microsoft store has the Mionix Castor mouse at $46 US (https://www.microsoftstore.com/store/msusa/en_US/pdp/Mionix-Castor-Optical-Gaming-Mouse/productID.332878900) or at 70$ CAN (https://www.microsoftstore.com/store/msca/en_CA/pdp/Mionix-Castor-Multi-Color-Ergonomic-Optical-Gaming-Mouse/productID.327736700). This was the best mouse according to Hardwarecanuck, Jayz2cents, etc. It's also RGB.
Also if you're a student, poke around their website to get a 10% discount, or search for a promo code on the internet. Ordered my Castor yesterday at 63$ CAN.
PS: Also free shipping and free return just in case