There are several types of bagpipes but I suspect you are referring to what we all commonly know as bagpipes , which is " the great highland bagpipe " and the bag size & the bag cover are pretty much universal .

Years ago , the great highland bagpipe could be ordered with an oversized bag as an option ( it may still be an option , I'm not sure ) thus the bag cover would be larger .

Other than that , I think it's pretty much your choice of tartan or solid color , choice of fringe color and as unixken mentioned the option of a grip panel on the outer side .

Best wishes to you on taking up the pipes !