Achipmunk,
Any Wilton "Bullet" style (the round cylinder ones you talk about) will have two different series. A rounded slide with a squared off/flat logo on the side is a cheaper version that they call their Tradesman. The Machinist series is their heavier duty line up, which sounds like the one you want.
If you come across a Wilton bullet at a yard sale or something, look around on it for a number designation, and the machinist series will be "400S" or 600 or whatever. If I remember right, a 400S would be a 4" wide jaws, with a S - Swivel base. 600S, 6" jaws and so on.
A Tradesman series will have a longer digit code, if I remember correct. "1760" and so on.
Also, if you decide to go with one of the more heavy duty brands like a vintage Reed, they utilize a 3 digit code as well (many other vintage brands used the same thing). Examples... 204... 103...206 and so on.
The first number will usually be a 1, 2, or 4. The 1s and 2s being most common, followed by the 4 and a few other more odd-balls that you'll rarely find.
The 1 means it's a stationary base (it'll be a 1xx)
2 means it has a swivel base. (2xx)
and 4 means it has a swivel base *and* the rear jaw swivels, like the Prentiss No 3. vise I linked in my above post.
The next number is virtually always a 0.
The last number is the width in jaws. 4 for 4", 7 for 7", and so on.
So if you see someone advertise a "Reed 204" vise... you'll know without seeing a picture, that the vise will have a swivel base (2) and will have 4" wide jaws.
A 105 will be a stationary (1) base, with 5" wide jaws, and so on.
Hope this helps.
