From a similar question on the forum earlier this year, I suggested:
Unfortunately, presets can be in lots of locations. For Vegas Pro window layouts, they are saved to C:\Users\your user name\AppData\Roaming\VEGAS Pro\19.0 (18.0/17.0/16.0 etc)
Third party presets are usually saved by default to that 3rd party company's folder under C:\Documents.
Under the Documents folder there might also be a folder named 'OFX Presets' which should include Vegas Pro VFX saved presets. Many of these folders have a subfolder named 'Presets'.
VST presets might also be found in C:\Program Files and C\Program Files (x86) under the 'VstPlugins' and/or 'Steinberg' folders.
There could well be other locations as well.
Folder path names may be different since your version of Vegas Pro 13 is from the old Sony days of Vegas Pro rather from the MAGIX releases of 14+.
I had some really cool ones made and I must have overwritten them on the preset manager or something.
If you've overwritten them on your older PC, then unfortunately they're gone. For the future, its a great idea to keep backup copies on another drive whether that be a memory stick/card or an inexpensive external portable hard drive. Not just for 'errors' (and I did experience an error yesterday) but also in case of a HDD/SSD failure - and that applies for all media and Vegas Pro .veg project files as well. If there is no backup, then everything is lost if an unexpected failure or error occurs.
And rename backup saves with something like 'v1', 'v2' etc - or whatever works for you.