Depending on how far you want to chase this, there is a whole flock of hawks waiting to be modeled.
In addition to the Hawk 75N (the "Thai Hawk") there was also the Hawk 75M (sold to China) and the Hawk 75O (sold to Argentina). These had slightly different wheel covers and armament.
There are also lots of variants of the the Hawk with retractable undercarriage.
Details:
Model 75B - prototype with Wright R-1820 engine
Model 75D - first prototype, Wright Whirlwind R-1670 engine
Model 75K - Unbuilt version, intended to use the Pratt & Whitney R-02180 Twin Hornet engine.
Model 75P - production P-36A (serial 38-010) fitted with Allison V-1710 liquid-cooled engine, prototype for Curtiss P-40
Model 75R - company-owned 75A temporarily fitted with R-1830-SC2-G engine with turbosupercharger, attained 330 mph (530 km/h) but proved complex and unreliable
Y1P-36 (Model 75E) - USAAC prototype, Pratt & Whitney R-1830 engine
P-36B - production P-36A fitted with an R-1830-25 engine producing 1,100 hp (820 kW), reached 313 mph (504 km/h), returned to original P-36A configuration
P-36C - an additional 0.30 in (7.62 mm) machine gun installed in each wing with external ammunition boxes under the wings, R-1830-17 engine with 1,200 hp (895 kW), last 30 production aircraft were completed as P-36Cs
XP-36D - production P-36A modified with 2 × 0.50 in (12.7 mm) machine guns in the nose and 4 0.30 in (7.62 mm) machine guns in the wings
XP-36E - production P-36A armed with 4 × 0.30 in (7.62 mm) machine guns in the wings, retained standard fuselage guns
XP-36F - production P-36A fitted with 2 × 23 mm (0.9 in) Madsen cannons under the wings, reverted to P-36A because guns imposed an unacceptable performance penalty with top speed of only 265 mph (427 km/h)
P-36G - Hawk 75A-8 used by Norway for training in Canada; later delivered to Peru. Wright R-1820-G205A engine with 1,200 hp (895 kW).
Hawk 75A-5 - built under license in China (production was later moved to India), absorbed into RAF as Mohawk IV
Hawk 75A-6 - version for Norway; aircraft captured during the German invasion were eventually sent to Finland
Hawk 75A-7 - version for Netherlands East Indies: 1,200 hp (895 kW) Cyclone, 4 × 0.303 in (7.7 mm) (two in nose, one in each wing) and 2 × 100 lb (45 kg) bombs.
Hawk 75A-8 - Export version for Norway. Later redesignated P-36G.
Hawk 75A-9 - 10 aircraft delivered to Persia, captured still in crates and used by RAF in India as Mohawk IVs
Hawk 75M - simplified version with fixed landing gear and Wright R-1820 Cyclone engine for China, built by both Curtiss and Central Aircraft Manufacturing Company in China
Hawk 75N - simplified version for Siam (Thailand)
Hawk 75O - simplified version for Argentine, 30 built and delivered by Curtiss with additional 200 to be built under license locally by Fabrica Militar de Aviones, however only 20 were completed.[2]
Hawk 75Q - two additional simplified demonstrators for China
XP-37 - Allison V-1710 liquid-cooled engine, cockpit moved to the rear of the fuselage
YP-37 - service test version of XP-37, 13 built
XP-42 (Model 75S) - testbed for streamlining cowlings around air-cooled engines