I'm interested in Roman swords, particularly the sparthas used later on during the Roman Empire, and how they inspired more modern longswords.
Firstly I'm looking for any further information about how they were used, but also I'm interested in where I would be able to find authentic spathas for sale. I've found a couple of old listings for some gorgeous, rustic swords but unfortunately no current sales. Does anyone have any ideas?

When you say "authentic" I assume you mean 16-17 hundred year old Roman weapons? These are in the realm of antiquities. You might try Hermann Historica, they sometimes sell similar things in their auction catalogues, I've never looked for a spatha per se, but I know they have sold Greek and Roman helmets in the past, so why not that. As a general rule though, you are looking for an excavated item with corrosion and significant loss of metal. I leave those to museums who have the resources to conserve and curate such articles. If I wanted an "authentic" spatha, I would buy a high quality reproduction forged by a present day smith as have appeared on these posts in the not too distant past. That would make it in the shape and condition that a 3d century Roman would have seen and perhaps carried, as opposed to something in relic dug-up, condition.
Henry

I just had another thought-in response to your query on how swords were used in ROME. There is a recent book I just finished reading, Rome and The Sword, by Simon James. Has a lot of information on what you appear to be asking about.
Henry

For a well researched and quality reproduction you can have a look at Albion Swords, Next Generation Swords:

http://www.albion-swords.com/

Specifically for a Spatha:

http://www.albion-swords.com/swords/albion/ne...spatha.htm

In the UK we have Hector Cole, Paul Binns and Owen Bush who are all capable of forging a spatha to very accurate period styles. Just depends on what your spec is.

Some options...

http://www.replik-online.de/en/index.html

http://www.forgeofavalon.com/index2.php?menu=celticsteel

http://www.forgeofavalon.com/index2.php?menu=...rds#swords

http://www.romanarmytalk.com/67-for-sale/3244...-sale.html

I think Albion Europe still have a spatha in stock http://albion-europe.com/swords/swords-by-tim...x?model=43

And there's another one here http://www.myArmoury.com/talk/viewtopic.php?t=32445

Anyone know a good Spathion?

I am not sure where to get a good Byzantine spathion these days like this one.
[ Linked Image ]

One of these days I might plunk down for something by Mark Morrow. He doesn't list prices for spatha, but I have no doubt he could do a fine job.

http://www.swordsmith.net/roman.html

Hey,

Auctions for an original.

For a reproduction that is epic, I second mark morrow
His url is just above