Newbie here starting my first A body

Welcome! 2K for a 69 dart as you described is not a bad deal. Most of the repop metal your going to need mostly all come from the same place just different venders. Shop around for best price. AMD and Goodmark are good places to start. If you can cut out the middle man is usually your best bet at a good price! Nothing wrong with building your 273 or up grading to a 318! The 318 is one of the most abundantly available and most under rated engines out there!!! We all know that there's no replacement for displacement! But on a tight budget you can build a nice combo on a 318 platform and have a blast doing it. It's been done 1000's of times just ask all of the tight budgeted guy's and gal's on this site. There's a combo for everyone just don't be afraid to ask any and all questions and someone here will have an answer for you! And post some pics as soon as you can!