Silen, as an example of what a good rhyming dictionary has, here are some of the "-AY-shun" words you requested, as taken from Whitfield's Untiversity Rhyming Dictionary. Numbers indicate the number of syllables.

The list continues for a bit more than eight columns; the text below is just the first column's worth.

2. nation, ration station 3. cibation, libation, limbation, jobation, probation, placation, vacation, peccation, plication, sulcation, truncation, location, vocation, furcation, piscation, gradation, foundation, laudation, sudation, creation, legation, ligation, rogation, purgation, jugation, striation, alation, halation, ablation, oblation, sublation, elation, delation, gelation, relation, velation, deflation, sufflation, inflation, conflation, dilation, vallation, illation, collation, prolation, cremation, sigmation, himation, gemmation, commation, summation, formation, planation, andation, enation, agnation, signation, cognation, domnation, conation, donation, phonation, pronation, lunation, libration, vibration, hydration, ceration, spheration, mguration, liration, oration, moration, nitration, titration, filtration, curation, duration, neuration, gyration, cessation, causation, pausation, natation, jactation, lactation, tracation, dictation, nictation, citation, saltation, peltation, cantation, plantation, dentation, mentation, tentation, floatation, notation, potation, rotation, quotation, votation, ccaptation, septation, flirtation, hortation, curtation, substation, gestation, testation, crustation, gustation, guttation, lutaation, mmuation, nutation, putation, equation, lavation, ovation, novation, starvation, nervation, servation, curvation, laxation, taxation, vexation, fixation, luxation, fluxation, 4. reprobation, approbation, perturbation, accubation, incubation, titubation, intubation, desiccation, exsiccation, deprecation, imprecation, comprecation, albication, radication, abdication, dedication, medication, predication, indication, vindication, syndication, replication, triplication, implication, complication, application, supplication, duplication, explication, varication, fabrication, imbrication, lubrication, rubrication, lorication, extrication, vesication, mastication, rustication, toxication, allocation, collocation ...