Lost Buttstock/ Battery end cap, where to get a new one??
 

To my joy, while unpacking my gear after a victorious day of battle. I noticed my battery/buttstock end cap was missing, and nowhere to be found. So I am going to have to get a replacement.
It is a CA HK53A2, same rear stock as an MP5A4, with the full rear stock.
Who would I need to go through, to order that part from CA? A Canadian retailer? or US, or HK retailer? Or could I get it through Spartan Imports. I know WGC has one , but I would like to avoid a $50. UPS shipping charge for a $7. part.
Thanks in advance for any suggestions.
Sorry mods , can you shift this to the right place. Meant it for parts/accessories discussion.