Per 13.501(a)(iii), the justification must be posted within 14 days of contract award. Because the justification is to be posted AFTER award, am I still required to post a combined synopsis/solicitation to meet the requirements of 5.201? Will a Notice of Intent to Award a sole source procurement meet the requirements of 5.201 if it states that all responsible sources may submit their technical capabilities, which shall be considered by the Government? Also, since Part 6 does not apply to Part 13.5, what should be listed as statutory authority permitting other than full and open competition? If Part 6 were applicable, it would be 6.302-1.
For your first question, yes, based on "solicitation" is in FAR 13.501(a)(iv).
Question 2, implied by 13.501(a)(i) - Conduct sole source acquisitions as defined in FAR 2.101, (including brand name) under this subpart only if the need to do so is justified in writing and approved at the levels specified in paragraph (a)(2) of this section: You still need to meet the J&A requirements of this section.
FAR 13.104 (b) If using simplified acquisition procedures and not providing access to the notice of proposed contract action and solicitation information through the Governmentwide point of entry (GPE), maximum practicable competition ordinarily can be obtained by soliciting quotations or offers from sources within the local trade area. Unless the contract action requires synopsis pursuant to 5.101 and an exception under 5.202 is not applicable, consider solicitation of at least three sources to promote competition to the maximum extent practicable. Whenever practicable, request quotations or offers from two sources not included in the previous solicitation.
If you are allowing contractors to submit technical capabilities then this is not a true sole source notice.
FAR Part 6 does not generally apply to contracts awarded using the simplified acquisition procedures of Part 13. See FAR 6.001(a). Therefore, FAR 6.301(b) also does not directly apply. For acquisitions below SAT conducted under Part 13, look to agency supplementation of FAR 13.106-1(b)(1) for any content requirements associated with the contracting officer's determination that only one source is reasonably available.
13.501 Special documentation requirements.
(a) Sole source (including brand name) acquisitions.
(1) Acquisitions conducted under simplified acquisition procedures are exempt from the requirements in part 6. However, contracting officers must-
(i) Conduct sole source acquisitions, as defined in 2.101, (including brand name) under this subpart only if the need to do so is justified in writing and approved at the levels specified in paragraph (a)(2) of this section;
(ii) Prepare sole source (including brand name) justifications using the format at 6.303-2, modified to reflect that the procedures in FAR subpart 13.5 were used in accordance with 41 U.S.C.1901 or the authority of 41 U.S.C.1903;
(iii) Make publicly available the justifications (excluding brand name) required by 6.305(a) within 14 days after contract award or in the case of unusual and compelling urgency within 30 days after contract award, in accordance with 6.305 procedures at paragraphs (b), (d), (e), and (f); and
(iv) Make publicly available brand name justifications with the solicitation, in accordance with 5.102(a)(6).
Your authority is in FAR Part 13 specifically FAR 13.106-1(b)(1).
Hope that provides the assistance you were looking for.