100-1000 or more depending on specifics
Yes there is 30-30 cal, 20" barrel. I have one.
$500
your question is not specific enough, .30 cal carbine can be anything, as for 1944 can also mean a very wide range of firearms. for the two I know of: M1 Carbine, .30 carbine caliber, semiautomatic carbine Inland - around $800 Mosin Nagant M44 carbine, manuf 1944 in very good condition (like if you bought "new" from a store) around $90. there are hundreds of ".30 cal carbine" that are also manufactured in "1944".
Ball, blank, tracer are a few.
Try oldguns.net
Name of who made it.
10-1000 USD or more depending on specifics
It is worth between $200 and $2,000.
175 or so
60-200 USD or so
100-1000 or more depending on specifics