I ordered mine on amazon. I'd also advise getting one with a tare function so that you can zero out the weight of the bowl, then add the snake and weigh.
Mine works well, but I think it only goes up to 500 grams, so I'll be needing a heftier model when my BP starts to grow.. My boa (whom I weighed for the first time last night) was 399 grams, so I guess I'd better start looking now.