Not to get off the subject of which snake to get..... But try and get all of your husbandry in place first. You will need a quality thermostat, thermometers, caging ( I would recommend a vision type setup that has the ability to stack in case you plan to add another snake in the future) and other misc. things to get started. Once you get that budget worked out, you'll know how much you have to spend on a snake.
Now to the type of morph.... I would look for the best looking female you can afford. No matter what morph you get, try and find the best example you can within budget, preferably from a reputable breeder. I would start at an expo to get an idea what sparks your interest. It's all about what you want to see in your cage!!