I don't see an easy way. I suggest using a horizontal bar chart. Works great for long axis tick values and bar labels., If you must have a VBAR,for a one of a kind graph with SAS 9.3, you could take the GTL code (from View->code) , and add DRAWTEXT statements. Or convert o an SGPLOT VBAR (very simple code), and add SGANNO for the bar labels.
Not as easy as Designer, but...FYI, rotated bar labels are coiming with SAS 9.4..