Good advice above.
First off, what do you want to use it for? Daily rider, Sunday cruiser, rally bike?
Keep in mind that Allstates were pretty much stripped down bottom of the line Vespas.
Three speed tranny, piston ported (maybe the only plus!) less than 5 bhp, no front dampener, 8-inch tires. In other words they are not speed demons or great handling or very comfortable to ride. Don't be surprised if you get passed by bicycles...seriously. Not pratical for a daily rider.
One good thing is that it is a large frame and not a widebody.
I will admit that I almost bought an Allstate handlebar, they do have a certain appeal
There are lots of Allstate fanatics. They know what they are getting into and accept them for what they are. I have a friend with a 63 Allstate and I can tell you it is a ton of fun to ride.
As far as rarity and collectability...well generally they are not very high on the list.
Here is a link to the specs
http://www.scooterhelp.com/scooters/all ... 94493.html
And some additional info
http://www.scooterlounge.com/vespa/buye ... ears.shtml
According to model no it is a 1958 or 1959
1958
engine: single cylinder, air cooled 2-stroke
induction: piston ported
bore: 54 mm
stroke: 54 mm
cubic capacity: 123.67 cc
compression ration: 6.3: 1
bhp at rpm: 4.5 @ 5000
lubrication:5%
transmission: 3 speed constant mesh
1st gear: 12.20: 1
2nd gear: 7.60: 1
3rd gear: 4.85: 1
cutch: wet - multiplate
carburetor: Dell'Orto UA/16S1
main jet: 72
slow running jet: 38
needle jet: 2.60
needle position: 2
throttle valve: No 50
ignition: contact breaker & coil
ignition timing: 28 deg. BTDC
breaker gap: 0.3 - 0.5 mm
voltage: 6 volt
wheels: 8"
tires: 3.50 x 8
max speed: 47 mph
similar to Vespa VNA1T but no front damper