The gun you are looking at is most likely an Italian Carcano.
Gardone VT ==Town of Gardone in the Trompia Valley. Site of a Government assembly Plant.
P.Beretta was (is still) situated in Gardone; Their rifles are fully marked "P.Beretta Gardone VT".
Both plants made M91/28 TS ( Short rifles)...the "TS" Model is NOT a carbine, as it was used by Non-cavalry troops (Engineers, Naval Infantry, Artillery, etc).
The rifles don't have a lot of value... however, like most military weapons of that era they are going up in value everytime you look at them.
Being military they actually use a "clip" and not a magazine. The clip holds 6 rounds, is inserted into the rifle from the top, and when the last round is fired the clip is ejected out the bottom.
Ammunition is not especially hard to find in 6.5.... they were also produced in 7.35 and that ammunition is very hard to find (I have mine done by a custom reloader) and very expensive. In the 6.5 the clips are actually more expensive than the ammunition if you can find any.
The gun is not particularly powerful compared with other military rifles of the same time but it was deadly. It was a 6.5 Carcano that killed Kennedy in Dallas. The rifles are also not known for pin point accuracy. The 6.5 bullet is the same as a .26 caliber. This is the bullet used in a .260 Remington.
It is slightly smaller than the bullet used in the .270 Winchester and the 6.8 SPC.
The guns can be fun to shoot if you spend the time and ammunition to learn where yours shoots. Most CCR holders and other military collectors would have one in their collections just because they are what they are... I have 2, a 6.5 and a 7.35.
If the gun is in any kind of reasonable shape it is worth $150 dollars.... like I stated they can only go up in value as the number available dries up.
Good Luck with it and if you buy it post a report on how it shoots.
Hope this helps you out a bit....