TGV from Paris (originating in Orleans) to Barcelona

check the site the man in seat 61 he may have some suggestions,.....

Although traveling via Paris is fastest and is billed as "one connection" on train schedules, it's actually two connections, including travel from Paris Austerlitz station to Gare de Lyon by taxi or subway. Instead of changing in Paris, I'd prefer a departure with two connections elsewhere, such as this example from the DB train schedules:
Orléans Mo, 05.05.14 dep 08:28 14044 Schnellzug
Les-Aubrais-Orleans Mo, 05.05.14 arr 08:32

Transfer time 15 min.
Les-Aubrais-Orleans Mo, 05.05.14 dep 08:47 3611 Schnellzug Subject to compulsory reservation,
Toulouse-Matabiau Mo, 05.05.14 arr 14:14

Transfer time 51 min.
Toulouse-Matabiau Mo, 05.05.14 dep 15:05 TGV 9735 TGV Subject to compulsory reservation
See http://www.ricksteves.com/travel-tips/transportation/trains/france-rail-passes#ticket-tips for Rick's tips on buying advance-discount tickets 3 months ahead through SNCF. You would not need to book the first, short connection (above) in advance, but could do the other two legs.

How are you going to get from Orleans to Paris Gare de Lyon to catch a 7:15 train? Driving would be the only option and the car rental agency better have a drop box.
You can check the real prices at the website at http://en.voyages-sncf.com/en/
Use France as your ticket collection country. June 7 shows a price of 223.40 euro total for 2 adults for the 7:15. That is $156 per person at todays exchange rate. On the other hand, if you take the 16:07 the price goes down to 118 euro for 2.
So don't use Rail Europe, and ask your self if you really need to get to Barcelona first thing. That would get you plenty of time to get to Gare de Lyon. From Orleans you'll arrive at Gare d'Austerlitz. Its about a half mile walk between them, or a taxi.

Not only is it a 15 minute walk between the two train stations, but it is also only a five minute bus ride across one bridge, easy enough for Paris.