Clearview is a good source for replacement shields. Gives you stock dimensions.
21.5" length: measured from the top of the headlight cutout to the top of the shield. Don't know how wide OE is (26"?), but their OE replacement is one inch wider. ($203 and up for taller) (generally thicker than stock and Clearview is Lucite/plastic, and I think OE is lexan) (you can get an adjustable vent for more money)
http://clearviewshields.com/shop/product.php?id=33Stock shield from HDL is:
(reuse the Honda mounts, whether for OE or aftermarket)
http://www.hdlparts.com/fiche_section_detail.asp?section=2137059&category=Motorcycles&make=HONDA&year=1997&fveh=124889Another aftermarket maker, also plastic. ($279)
http://www.ceebaileys.com/honda/valkyriews.htmlThe best Lexan you can get. ($330) (supposedly can be scrubbed with steel wool and not scratch)
http://www.f4customs.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=GLNTD-HVN57KAPANP&Category_Code=VALKTOURHDL has a bunch of others, but none are better, and these you have to buy the mounts as well (I think).
http://www.hondadirectlineofshadyside.com/stores/byProduct.asp?prd=Windshields&str=2&ID=553003918