Good afternoon Calikatoom,
Yes, there are some options. The Garmin Zumo and Garmin Montana series are going to be best in class GPS devices.
For the price range you are looking at, and street motorcycle oriented, you will want a Garmin Zumo 220. Retail is $399 and can be purchased for around $369 with some searching. That unit was discontinued in the last few weeks which will be reflected on major websites shortly. If you look quickly, you can get a "new in box" unit by Christmas. Strategically, buying recently discontinued units may not be the best direction to go in for future support and compatibility but, will work if necessary.
The Garmin Nuvi 500/550 is a non Zumo version of the physical Zumo 220 unit. The OS and features are different as well as not having the mounts for motorcycles included. However, it can be used as a Zumo light.
The Montana is a great choice and any of them 6xx will work but will be more of a long term investment.
A used garmin Zumo 660 or 660LM would be a good choice.
Finally, a new Garmin Oregon 550 can be used on a motorcycle. Oregon 450 as well (without the camera). A new in box unit is $350 and with a CNNT map and some mounting hardware, it will work both on the street, trail and hiking. It was the best in class unit for this prior to the arrival of the Montana 6xx series.
River Pilot Tours
Cheyenne, WY. U.S.A.
PH: (01) 307-222-6347
GPS Software Titles: http://shop.spotitout.com