Westbrook, Moats, Perry and Mahe all are undersized backs. Buckhalter has missed three of the past four seasons with knee injuries and could be a long shot to make the roster.
The popular opinion is that the Eagles need a bigger back for short-yardage situations. But it clearly isn't high on Reid's priority list.
"I don't mind having a back with a little bit of size," he said. "I don't mind having a changeup guy in there. I always keep my eye open for that. All our (top three running backs) are similar. If there's a big guy out there we can mix in like we have in past years, I'd look at that. But I also can fit the other three in."
The 5-9, 200-pound Westbrook is a talented runner, but he has major durability issues. He hasn't made it through a season healthy since the Eagles drafted him in 2002. He missed the final four games of last season with a Lisfranc sprain in his foot.
He's got just two 20-carry games in his career and has had more than 21 touches in a game just six times. A number of his injuries have come after a heavy workload.
But Reid insists he has no hesitation about heading into 2006 with Westbrook as his go-to ball carrier.
"He's the lead dog," he said. "He's going to get the ball. (In the) running game. (In the) passing game. He'll be fine. He's probably trained harder (this off-season) than he ever has."
That said, Reid likely will continue to monitor Westbrook's touches and rotate him with Moats and probably Perry. It's still not certain what the 6-1, 240-pound Tapeh's role will be, but it's likely he'll be used more as a fullback than a running back.
"We saw some good things out of the other guys we put in there last year," Reid said. "If anything positive came out of that last half of the season, it's that we got to see some of those young guys play."
Moats, the Eagles' 2005 third-round pick out of Louisiana Tech, averaged 5.1 yards per carry and had three touchdowns in the Eagles' final six games. Perry averaged 4.6 yards per carry after being signed off the practice squad, and rushed for 70 yards on 15 carries in the Eagles' final regular-season game against Washington.