@kevin, the trick to having the tape size match the PDF page size is to paste the copied DeskCalc tape into a Microsoft Word document, then change the Word page size to match the page size of the DeskCalc tape. Then save the Word file as a PDF, and your PDF with the DeskCalc tape will be the correct size. Using Microsoft Word adds an extra step to the process, but will give you the results you desire.
This is the first time I’ve heard of DeskCalc, so haven’t actually used it in my tax business (I typically always use Excel). However I’ve used this Word trick to resize PDF’s for many other types of documents that needed resizing. Hope this trick is helpful.