WhiteAstro, I was going only by some images I've seen on the Internet where they looked very similar.There is a differance in construction between the Sirio & the Workman Star Dusters. Download the Owners manual for each and you'll see the differances.
I have Sirio manual, but I look around a little and did not find the Workman manual available. If you have a copy, just post it here in this thread, and I will get a copy, you are probably right.
Thanks in advance,
Eddie - Marconi