What a great find (and luck) you had 😀 it indeed looks like it's a 2998-1, according to Moon Watch Only (MWO) the serial 17301XXX are only under this reference and the 2nd hint in my opinion is the flat dial... Your dial, again in MWO, is the A4 Shorts markers - Round O... this dial existed both flat and stepped. We know 2915 had only flat dial so my guess is the first dials of the 2998 were also flat before they added the step on it. Of course no chance it is a 2915-1 due to the dial, bezel, hands... nonetheless you have an amazing watch that deserves a lot of attention.
The lume looks absolutely gorgeous but something is bothering me if I may about the hands... I am no 2998 expert but using my beloved MWO and speedmaster101 (thanks again William) the minute hand looks curved which is a good thing, but the hour hand seems to be a later edition as per the squared end of lume, which makes me suppose these are later replacement but still original Omega.
They perfectly match the lume of the dial so 3 options here: these hands are originals 😀 which gives us (or just me) a new indication about this handset, or they have been changed very early in the lifetime of the watch which would explain they have the same patina like the dial, or these are later replacement which have been relumed with the dial (very very very well done in this case) but let's call the experts about alpha hands because I am again definitely not one of those