The direct replacement part for the Mark IV fan is
Globe Motors
A47-B15A-15T1-100
You can buy this on line at Allied Electronics. Here is a link to this item.
http://www.alliedelec.com/Search/ProductDetail.asp?SKU=965-1215&SEARCH=&MPN=A47%2DB15A%2D15T1%2D100&DESC=A47%2DB15A%2D15T1%2D100&R=965%2D1215&sid=46D214003630617F
They also have the power cord for this at Allied. Do a search for "Globe Motors Power Cord".
Hope this helps.