Here is a list of veterinarians in your state that are members of the Association of Reptile and Amphibian Veterinarians. This doesn't necessarily mean they are qualified to treat your rhino viper but atleast they have some interest in herps. I would start calling the vets on this list and see if any of them treat venomous snakes.
Good luck,
Chris
Dr. Judy Rutkowski
Allentown Animal Clinic
2640 Walbert Ave
Allentown, PA 18104
Dr Kathy W. Liez
Rothman Animal Hospital
1309 Gainsbora Cir
Bala Cynwyd, PA 19004-2011
Dr Geoffrey H. Wright
Wright Vet Medical Center
3247 Wimmer Rd
Bethlehem, PA 18017-3334
Dr Gloria J. Goodman
4342 School Ln
Brookhaven, PA 19015-1514
Dr Denis Lee Daman
101 Thorncrest Dr
Butler, PA 16001-3932
Dr Patricia MacCabe-Laduke
Canadensis Vet Clinic
RR 1 Box 4088
Canadensis, PA 18325-9801
Dr. Toby Erlichman
938 Kings Arms Dr.
Downingtown, PA 19335
Patricia A. Schweibenz
320 West Sandy Ridge Rd.
Doylestown, PA 18901
Christopher Montgomery
2 Bloomfield AVE APT 12
Drexel Hill, PA 19026-5418
Dr Mark Madzy
VCA Delaware Valley Animal Hospital
266 Lincoln Highway
Fairless Hills, PA 19030
Dr Christina J. Mackensen
2361 Sugar Bottom Rd
Furlong, PA 18925-1202
Dr Edward R. Bennett
All Pet Animal Hospital
5007 Route 8
Gibsonia, PA 15044
Kristine Vennen
All Pet Animal Hospital
5007 Rt 8
Gibsonia, PA 15044
Dr Jennifer F. Johnson
Glenolden Animal Hosp
405 S MacDade Blvd
Glenolden, PA 19036-2007
Kathleen McCloskey
Franklin Veterinary Associates
2380 Buchanan Trail West
Greencastle, PA 17225
Dr Johanna Lee Vena
528 Waterfall Drive
Johnstown, PA 15906
Dr Bridget McMahon
Kutztown Animal Hosp
7 S Kemp Rd
Kutztown, PA 19530
Dr Barry A. Harris
2497 A Old Philadelphia Pike
Lancaster, PA 17602-3461
Dr William M. Lewis
Smoketown Veterinary Hospital
at Bridgeport
1251 Ranck Mill Rd
Lancaster, PA 17602
M. Borden Loving DVM
Lewisburg Veterinary Hosp
829 Fairground Rd
Lewisburg, PA 17837
Esteban Polorny VMD
2179 Smoketown Rd
Lewisburg, PA 17837
Dr. Joseph J. Hyduke
Malvern Veterinary Hospital
545 S. Warren Ave.
Malvern, PA 19355
Dr Kathy Tracy
Conchester Animal Hosp
530 Conchester Hwy
Marcus Hook, PA 19061-3104
Dr Pamela Jennings
VCA West Shore Veterinary Hospital
719 Limekiln Rd
New Cumberland, PA 17070-2317
Dr William R. Belzer
Box Turtle Conservation Trust
304 East Bissell Ave
Oil City, PA 16301-2004
Dr Richard C. Hann Jr
Palmyra Animal Clinic
920 E Main St
Palmyra, PA 17078-1914
Dr. Todd G. Rubey
Palmyra Animal Clinic
920 E. Main Street
Palmyra, PA 17078
Dr. Keith C. Hinshaw
Philadelphia Zoo
3400 W. Girard Ave.
Philadelphia, PA 19104
Dr Donald W. Stremme
Center City Animal Clinic
1129 Pine St
Philadelphia, PA 19107-6035
Dr R. Avery Bennett
738 S Mildred St
Philadelphia, PA 19147
Michael J. Balsai
107 N Mole ST
Philadelphia, PA 19102-1404
Karen Rosenthal
University of Pennsylvania
3900 Delancey St
Philadelphia, PA 19104
Dr James K. Beebe
Northview Animal Hosp Inc
223 Siebert Rd
Pittsburgh, PA 15237-3738
Dr Cynthia Stadler
10 Glenview Dr
Pittsburgh, PA 15237
Dr Robert Wagner
University of Pittsburgh
S 1049 BST
Pittsburgh, PA 15261
Dr. Carolee Switalski
Pittsburgh Zoo
One Wild Place
Pittsburgh, PA 15206
John A Coniglario DVM
2907 Walnut Ridge Estates
Pottstown, PA 19464
Dr Liza Clark
Quakertown Vet Hospital
2250 Old Bethlehem Pike
Quakertown, PA 18951-3948
Dr. Patricia Slanga
684 Ridge road
Spring City, PA 19475
Dr Karen Jones-Diller
PO Box 235
Spring Mills, PA 16875-0235
Kendra E. Stauffer, DVM
546 Dupont Ave
York, PA 17403