Classic/Antique Car Repair: 1968 VW Beetle LH vent window, vent window, window seals

Question
The knob is gone and the knob bracket is still spot welded to the vent window
frame.  How do I replace the knob?  Do I have to replace the entire vent window?  
Where can I find replacement.  Thanx.

Answer
Robb,
 Sorry for the delay.  

I haven't done one, but I believe the latch bracket is riveted.  If so, you'll just have to drill it out.  See here for the an example on a bus:

www.vwheritage.com/vwh/Bus-Parts-1968-79%5CBody%5CCab-Doors%5C?templateID=vwh

Scroll down to:
Door Window Seals & Opening 1/4 Lights
Item #8




Rick