I am building a model for reading receipts from their mobile snapshots. After the receipt is OCR'd, I plan to use a variation on LayoutLM for entity extraction. Entities are: "quantity", "price-per-unit", "product-name", "items-price", etc.

What is the best model to consider to link all these entities into a single receipt item, so the final result looks like:

"items": [
   {"product": ...,
    "unit_price": ...,
    "price_paid": ...,
    "quantity": ...,