If you're having trouble maybe just sold out for this year, this is not usually a rare item at all. But supplies of specific plants always vary from year to year and location to location.

The two locally common, familiar ones of similar compact, snow-resistant habit are 'St Mary'* and 'Victoria'. 'St Mary' has a straplike leaf with good indumentum, 'Victoria' has a pointy leaf with added bonus of conspicuous pink sheathing at first, suggestive of a rubber plant (Ficus elastica). 'St Mary' tends to look more substantial, 'Victoria' more perky.

*Of west coast commerce, Seattle arboretum has a different plant under this name

I've seen Victoria around a lot, but I think this is a much larger variety?

No, if anything the other way around. A. Jacobson, NORTH AMERICAN LANDSCAPE TREES notes that 'St Mary' "has a bushy crown but is no dwarf: the original* was 55' x 5'6" (1961). 'Victoria' was 37' x 4'3" x 31' in Seattle during 1993. Another, planted at the OSU experiment station south of Portland in 1967, measured 27' x 4'5 1/2" x 34' the same year (1993).

Magnolia table in Sunset WESTERN GARDEN BOOK says in 'Height' column that 'St Mary' grows 20 ft. but gets bigger when old, and 'Victoria' grows 20 ft. These are ballpark figures given for sake of expediency, as always.

*May not be the same clone as one commonly sold on west coast

Here is a link that might be useful: Tree Heights

Hmm..thanks for the info. I've done some further research, and see that some references have 'Victoria' at 20ft. It's frustrating how sources can vary. Some say that it is a "large tree." And St Mary is usually described as a "compact" variety at 20 ft - one even states "large shrub or small tree." Some sources state 'Victoria' has large 10" flowers while another says "small flowers."
I have been saving a spot in the garden and want to get the best tree for the site.

Neither has big flowers as far as the species goes, other common cultivars like 'Samuel Sommer' produce much bigger ones.