Supplier Page from Thermo Fisher Scientific for Niobium slug, 6.35mm (0.25in) dia x 6.35mm (0.25in) length, 99.95% (metals basis excluding Ta)
2-Ethoxyethyl ether, 98+%, extra pure from Thermo Fisher Scientific
Ethyl chloroacetate, 99% from Thermo Fisher Scientific
Ethylene carbonate, 99+% from Thermo Fisher Scientific
Ethylmercurithiosalicylic acid, sodium salt, 97.0-101.0% from Thermo Fisher Scientific