I would call a Husqvarna rep directly. Houzz forums are used primarily by home remodelers, and there are a few quilters who occasionally post here, but it is not primarily a place to find in-depth sewing and mechanical assistance.

Are you talking about an embroidery arm for the Designer 1? The machine has been discontinued for quite a few years, so the only way you could acquire one is to check with a sewing machine dealer who sells used machines. Since the resale value of the machine would be higher with the embroidery arm, it's unlikely you'd find anyone willing to sell just the arm unless the machine is toast, but you can try.

You might ck ebay...over and over! The embroidery unit will be rare fine, but it is possible there might be one out there that is unused. Some buy the machines and end up only using to sew with.