Custom Stamp as bar button

Here is an image that might make it more helpful with what I am trying to do. Currently I am using PDFTron system PTCheckMarkStampCreate and PTCrossMarkStampCreate to create a UIBarButtonItem by calling toolGroupManager.createItem(forToolClass: PTCrossMarkStampCreate.self)

How would I either override those to be my own custom image or how would I create my own stamp to add it to my toolGroupManager.annotateItemGroup .

I would like to make them look like this instead.
Screen Shot 2022-08-04 at 9.20.18 AM

Is there a way to override PTCheckMarkStampCreate and PTCrossMarkStampCreate too look like this? Or do you have example of how I can create a new stamp. Thank you