1026 DOM and JIS G3445 STKM 13, 14 A/B/C

Dear Friends :
I received couple prints from the States which need 1026 DOM tubes( ASTM A513 ). I have tried almost all the tube manufacturers in Taiwan. But only very few positive responses returned… Some of them even told me a 50 tons minimum volume will be needed. Since they have to purchase coil from CSC.
I wonder if any frined here have a idea about this “special” tube in Taiwan. G3445 STKM 13,14 in fact is corresponding to 1017 only. Not even 1020. But this is the highest class I can find here. My parts is about 100 to 150 mm long. Outside diameter varies from .875 to 1.000. Thicnkess is about .16. EAU is about 6000pcs each. Please kindly advise me some suggestions or if your plant exactly manufacture this.
Thanks in advance.