Try something like this:

select distinct tempcheck_id, record_id

from #tempcheck

inner join

(select tempcheck_id, min(record_id) as min_id

from #tempcheck

group by tempcheck_id) Sub

on main.tempcheck_id = sub.tempcheck_id

and main.record_id = sub.min_id

except

select t1.tempcheck_id, t1.record_id

from #tempcheck t1

inner join #tempcheck t2

on t1.record_id = t2.record_id

and t1.tempcheck_id < t2.tempcheck_id

and t1.item = t2.item

and t1.i_desc = t2.i_desc

and t1.s_desc = t2.s_desc

and t1.m_desc = t2.m_desc

inner join #tempcheck t3

on t1.record_id = t3.record_id

and t2.tempcheck_id < t3.tempcheck_id

and t1.item = t3.item

and t1.i_desc = t3.i_desc

and t1.s_desc = t3.s_desc

and t1.m_desc = t3.m_desc

You may need to play around with the join criteria to get exactly what you want, but it should put you in the right direction.

I noticed you have four of some record IDs. The above code will find if any three of them match, ignoring and unmatched fourth record. If you want to include unmatched fourth records, create a second query that extends the joins by one.