No, unluckily this is not possible, PR papers is an archetypal "proposal" which has constricted options, this needs to beryllium looked astatine wrong the PO (and not PR) context:
> What I deliberation whitethorn assistance present is to recognize the intent of each of the PR transactions:
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ME51N > Create PR
ME52N > Update / Edit PR
ME53N > Read-only entree to PR.
> ME51N and ME52N volition some let editing / saving, ME53N volition beryllium read-only.
(PO transactions volition beryllium likewise "split", but immoderate fields tin beryllium obscured / locked with your ain logic successful BADI ME_PROCESS_PO_CUST oregon other, and redeeming volition beryllium required).
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For the stated requirement, you tin lone person 1 (ability to alteration and save) oregon the different (read only), unluckily determination is nary artifact to redeeming (while redeeming is needed to determination the papers to the adjacent stage).
There is nary User Exit / BADI for PRs, arsenic they are lone *intermediary* documents - an intention to bargain which is past converted to PO (which is the main document).
If the request to parkland documents is required, they indispensable make the PO and usage the parkland enactment (if available), past look to fastener the field(s) they privation via User Exit / BADI coding, consult with your in-house ABAPers to realise this if they truthful choose;
*or*
Don't person the PR to PO until they are acceptable to order.
Hope this helps!