Amazon.com: Structural Pipe Fitting, 1-1/2" Wall Flange - Triangle, 51B-8, Aluminum Magnesium, Please note. ID of fitting is 1.925, to take nominal 1-1/2" steel pipe which all have an OD of 1.9". :
Amazon.com: M6-1.0 x 12mm Hexagon Flange Hex Bolts Flanged Screws, 304 Stainless Steel 18-8, Plain Finish, DIN 6921, Full Thread, 40 PCS : Industrial & Scientific
Amazon.com: M6-1.0 x 12mm Hexagon Flange Hex Bolts Flanged Screws, 304 Stainless Steel 18-8, Plain Finish, DIN 6921, Full Thread, 40 PCS : Industrial & Scientific
Stainless Steel 316 Grade Floor or Wall Base Flange for 2 x 2" Post - - Amazon.com
uxcell 5mm Inner Dia H15xD15 Rigid Flange Coupling Motor Guide Shaft Coupler Motor Connector for DIY Parts Black 4pcs: Amazon.com: Industrial & Scientific