I started looking at Doo Woppa Do with the obvious choices...Danzig and sons of Mr P over Buckpasser mares, and rapidly diverged into the not-so-obvious. Sorry this is so long-winded, as I was typing pretty much what I found as I did the research.
1. Langfuhr. Proven miler speed, works with just about any bloodline around but seems to like extra Northern Dancer, has two blacktype runners this year with Roberto (one w/Kris S and one w/Red Ransom). Dirt or turf, long or short. Has a very good winner bred similarly to Doo Woppa Do:
http://www.pedigreequery.com/travel+city2 As a bonus, if you get a filly, he's a much better than average broodmare sire.
2. Belong to Me. Also very consistent, miler speed, and an above average broodmare sire. Of the two, I think Langfuhr is the better stallion (more starters, more winners, more SW, higher earnings)...however, B2M isn't that far behind, and stands for $10,000 less.
3. Petionville. This guy is a straight-up racehorse sire, with 82% runners and earnings in line with Belong to Me. If you run him through TrueNicks this gets a D, but in this case I wouldn't worry too much--El Prado has 12 foals in the database who are older than 3, five of whom earned more than $100k. Medaglia D'Oro has a Gr-1 winner out of a STG mare, so that reverse cross is also working in limited attempts. What is a concern is that most of Petionville's best runners have a cross to Seattle Slew in there, which DWD does not.
4. The next one is a little out of the box, not to mention a little out of your price range...More Than Ready. He's throwing speed, and especially early speed. He's also thrown the winners of the 12f Victoria Derby, the 9f Canadian Stakes, and the 8.5f Fantasy Stakes, so he's not just a one-dimensional speedster.
What's really interesting about MTR, aside from some very good stats and the fact that he's done good things with all kinds of mares by all kinds of stallions, is his damline: he's out of a Woodman mare out of a Naskra mare. There's your classic-bred Mr P, but with Naskra you get a relatively uncommon bloodline that has been
very fruitful with both El Prado and Dynaformer. (Medaglia D'Oro has one foal out of a Naskra mare, who is racing in Russia.) El Prado has several winners out of Naskra-line mares, including one who won over $500,000. Dynaformer has it even better--4 graded stakes winners with Naskra within 4 generations, including Perfect Drift and Purim and millionaire Mystery Giver. If his fee drops into your price range, or you can get a share or a season to him, definitely have a look.
5. And now to go even further outside the box: Darley resident geezers Quiet American and Holy Bull and Adena rising star Macho Uno.
Medaglia d'Oro and El Prado both have this thing for horses bred similarly to Dr. Fager--Rachel Alexandra is out of a granddaughter to Cure the Blues; El Prado is 11 for 16 out of mares by Holy Bull, Great Above, Housebuster, and Quiet American, including a millionaire, two who won over $700k, and 2 who won over $250k. Wow. For his part, Dynaformer is 9 for 13 out of mares by Dr Fager or Dr Blum, including a Gr-1 winner, a horse who was 2nd in the BC Juvie, and 5 more who won more than $110k. His foals out of Holy Bull mares are 3 and 2, and out of 4 foals out of 2 different QA mares, one is unraced, one is 3, one is 2, and the other is a nonwinner.
Of those three--Quiet American, Holy Bull, and Macho Uno, I'd probably go for QA, as he'll be 25 next year. He's good at siring sound, hard-trying, hard-knocking horses who like to run and like to win. If you get a filly, you're in the cream for a broodmare prospect.
(edited to fix typos)