Cowan’s charges are heading to Brisbane Road for the first leg on Saturday, March 16 and welcoming them to the New Bucks Head the following weekend.
Orient are the favourites to win the competition but Cowan, who played for them as a schoolboy and had a spell under their chief Justin Edinburgh at Grays Athletic, would not have it any other way.
When asked what his initial feeling was when the draw was made, Cowan said: “Just a lot of excitement, really.
“You’ve got to play the cards you’re dealt, and it’s the toughest test we could have had. But every team at this stage of the competition is going to be a good team.
“We’re excited and looking forward to testing ourselves against a top side.
“It was Solihull Moors at the weekend, and we won.
“And even if it wasn’t them, I still would’ve said that if our lads are at it, we’re capable of beating any team in non-league.
“We know it’s going to be difficult, but it’s one we’re excited about.”
Orient made it to the semi-finals by beating last year’s winners Brackley Town 2-1 this past weekend.
Telford, of course, did so with a pulsating victory by the same scoreline at Solihull Moors.
On taking on a team who were League One title contenders just five years ago, Cowan added: “It’s just a massive, massive tie, isn’t it?
“I was there as a schoolboy as well, and I’ve played under Justin so I’ve got an idea what they’re about.
“I was there for a few years as a young kid. I played for quite a few of the London teams, with Orient being one of them.
“Ledley King and Nicky Shorey were there at the time.
“They’ve got an amazing history, which we’re very respectful of while knowing we can beat anyone on our day.”