Hi davor_k
If you are a Part 145 organisation with A ratings there should be a procedure in your MOE (normally in section 2.16 - release to service procedure) that needs to be followed in order to re-release serviceable components removed from an EASA aircraft. This would allow you to issue a Form 1 under your A ratings without the need to send your component to an approved workshop. If there is no procedure in your MOE you need to draft one and get it approved by the competent authority before performing any work on the component, or you can just send it away to an approved organisation. Have a look at AMC No 2 145.A.50(d), I think the following section can be useful to you.
AMC No 2 145.A.50(d) Paragraph 2.6
2.6 Used aircraft component removed from a serviceable aircraft.
2.6.1 Serviceable aircraft components removed from a
Member State registered aircraft may be issued with an EASA Form 1 by an appropriately rated organisation subject to compliance with this subparagraph.
(a) The organisation should ensure that the component was removed from the aircraft by an appropriately qualified person.
(b) The aircraft component may only be deemed serviceable if the last flight operation with the component fitted revealed no faults on that component/related system.
(c) The aircraft component should be inspected for satisfactory condition including in particular damage, corrosion or leakage and compliance with any additional maintenance data.
(d) The aircraft record should be researched for any unusual events that could affect the serviceability of the aircraft component such as involvement in accidents, incidents, heavy landings or lightning strikes. Under no circumstances may an EASA Form 1 be issued in accordance with this paragraph 2.6 if it is suspected that the aircraft component has been subjected to extremes of stress, temperatures or immersion which could affect its operation.
(e) A maintenance history record should be available for all used serialised aircraft components.
(f) Compliance with known modifications and repairs should be established.
(g) The flight hours/cycles/landings as applicable of any service life-limited parts including time since overhaul should be established.
(h) Compliance with known applicable airworthiness directives should be established.
(i) Subject to satisfactory compliance with this subparagraph 2.6.1, an EASA Form 1 may be issued and should contain the information as specified in paragraph 2.4 including the aircraft from which the aircraft component was removed.
Hope it helps.